The present invention refers to a set of X-ray film holders for taking exposures of an entire tooth, comprising holders for apical exposure of the side teeth as well as for apical exposure of the front teeth.
In order to obtain as accurate, that is as undistorted pictures of teeth as possible, it is necessary, on one hand, to bring the X-ray film provided in a holding device into the correct position, and on the other hand, to position and adjust the X-ray tube correctly with respect to the X-ray film. A film holder having a centering device is known from U.S. Pat. No. 3,003,062, whereby all teeth can be X-rayed. This is achieved by a shank of the holder which is rotatable in its plane in order to allow exposures of either the right or the left side of the mouth, or of the lower or the upper teeth, respectively. This film holder, however, is intended for a very particular type of X-ray tubes. A pluggable member, together with a cotton pad, is used as a bite portion. Moreover, this holder has to be dissembled and reassembled for every different application.
Another holder for the exposure of all teeth is known from European Patent Application no. 078 425, this holder being assembled in a modular form from the most diverse components which have to be rearranged according to the particular needs.